Manufacturing processes for automobile frames are evolving from one that currently utilizes MIG welding processes, i.e. an arc welding process in which a line of molten material is deposited by the welder in joining two pieces of metal together, to a spot-welding process. Spot-welding, a process involving the passage of electrical current between two electrodes to melt and join two pieces of metal placed between the electrodes, is being utilized in a greater degree in the manufacturing of automotive vehicles. Spot-welding requires a frame design that is conducive to being assembled using the spot-welding process. For example, if two tubular members are being spot-welded, access to the adjoining walls of the two tubular members by the spot-welder electrodes must be provided. MIG welding, on the other hand, is not compatible with a high production assembly plant. MIG welding, however, can be used for sub-assembly operations at a supplier level.
Automotive shock absorbers are vehicle components that absorb road forces encountered by the wheels of the vehicle. The shock absorber is physically connected to the wheel structure and is supported against the automobile frame to resist the action of the shock absorber. Conventional support of the shock absorber includes a front apron and a rear apron that help resist road forces.
Crash protection is also an important design consideration for an automobile frame as industry requirements provide that certain crash forces must be absorbed within the frame to protect the occupants. Improvements to the vehicle frame to better support the shock tower can also enable the steel front apron to be replaced by a plastic apron that can be utilized as a modular subassembly while also providing improvements to absorb crash forces.
U.S. Pat. No. 6,655,728, issued to Maki Sano, et al on Dec. 2, 2003, discloses the use of two seamless frame members fabricated from extruded aluminum alloy or magnesium to support an automotive shock tower. Similarly, U.S. Pat. No. 5,466,035, issued to Ulrich Klages, et al on Nov. 14, 1995, teaches a wheel housing support that is connected to a brace and a pillar by welding, although adhesive or rivets may alternatively be utilized to make the connection.
U.S. Pat. No. 5,024,482, issued to Hayatsugu Harasaki, et al on Jun. 18, 1991, discloses that the apron and the shock tower can be joined by welding. After the elements are joined together, the combined unit is welded to the seamed tubular member and the U-shaped reinforcing member. In U.S. Pat. No. 5,102,164, issued to Mitsuru Fujinaka, et al on Apr. 7, 1992, the apron and shock tower is supported between an upper seamed tubular member and a lower tubular connection formed by the tower and the U-shaped member.
U.S. Pat. No. 5,031,958, issued to Hideharu Fujita, et al on Jul. 16, 1991, discloses the formation of a tubular reinforcing member from two independent members. The shock tower is formed by two additional members. In U.S. Pat. No. 4,542,934, issued to Nobuhiro Komatsu, et al on Sep. 24, 1985, the apron is supported on two tubular members which can be spot-welded, as is noted in the paragraph spanning columns 4 and 5 of the patent.
U.S. Pat. No. 4,919,474, granted to Ryoichi Adachi, et al on Apr. 24, 1990, teaches a further example of an apron and shock tower formed by multiple members or elements. These elements are connected to form the apron and are attached to the frame of the vehicle.
None of the cited prior art teaches a shock tower support framework that utilizes hydroformed members that are spot-welded to provide support for the shock tower, with the frame support extending horizontally to connect to the upper vehicle frame and can be spot-welded to the lower vehicle frame in a T-configuration to improve crash resistance while providing an excellent support for the resistance of road forces by the shock absorber, thus providing a frame design that can be assembled in a high production assembly plant.